1. Field of the Invention
The present invention generally relates to the field of actuators. More particularly, the present invention relates to a hose piston which is adapted to be moved inside a flexible hose under a pressure difference, which in turn causes an external device to travel along the flexible hose by the movement of the hose piston.
2. Description of the Prior Art
Generally, pistons which are adapted to move in a straight path within a cylinder by fluid pressure and which are further provided with a transmitting member which can be moved by the piston through movement of the piston have been known in the prior art for many years. One problem with these piston cylinders is how to effectively seal a cylinder slot through which the transmitting member passes. These prior art applications require a sealing member for sealing the slot as the transmitting member is passed through.
In such cases where relatively large forces are required to be overcome in propelling a member along a given path, such as in elevator or conveying systems, any leakage of the pressure fluid past the piston will operate to lessen the effectiveness of the propelling apparatus and in some instances may prevent the accomplishment of the desired results.
One of the disadvantages with prior art pistons is that they can only move in a straight path and are not adapted to move in a combination of straight and curved paths. Another disadvantage is that the piston is not flexible to maximize the efficiency of the piston inside the cylinder. Another disadvantage is that these prior art systems can only be utilized in a short range application.
The following eleven (11) prior art patents were uncovered in the pertinent field of the present invention:
1. U.S. Pat. No. 2,473,430 issued to Hoffar on Jun. 14, 1949 for "Piston Coupling Mechanism" (hereafter "the Hoffar Patent"); PA1 2. U.S. Pat. No. 2,483,088 issued to Haven on Sep. 27, 1949 for "Tensioning Device For Producing A Linear Pull" (hereafter "the Haven Patent"); PA1 3. U.S. Pat. No. 2,695,694 issued to Seinfeld on Nov. 30, 1954 for "Diaphragm Mechanism For Pump Clutches" (hereafter "the Seinfeld Patent"); PA1 4. U.S. Pat. No. 3,019,813 issued to Dommann on Feb. 6, 1962 for "Conduit Provided With Movable Fitting" (hereafter "the Dommann Patent"); PA1 5. U.S. Pat. No. 3,045,611 issued to Murray on Jul. 24, 1962 for "Fluid Pressure Devices" (hereafter "the Murray Patent"); PA1 6. U.S. Pat. No. 3,421,718 issued to Gehringer et al. on Jan. 14, 1969 for "Integral Seal For Aircraft Launching Cylinder" (hereafter "the Gehringer Patent"); PA1 7. U.S. Pat. No. 3,504,872 issued to Russell-French on Apr. 17, 1970 for "Sealing Apparatus For Aircraft Catapults" (hereafter "the Russell-French patent"); PA1 8. U.S. Pat. No. 3,820,446 issued to Granbom et al. on Jun. 28, 1974 for "Means At pressure Fluid Cylinders" (hereafter "the Granbom patent"); PA1 9. U.S. Pat. No. 4,176,683 issued to Leibinsohn on Dec. 4, 1979 for "Flow Regulator" (hereafter "the Leibinsohn patent"); PA1 10. U.S. Pat. No. 4,266,751 issued to Akhavi on May 12, 1981 for "Stripper Clamp" (hereafter "the Akhavi Patent"); and PA1 11. U.S. Pat. No. 4,838,147 issued to Grishchenko on Jun. 13, 1989 for "Pressure Fluid Actuator"(hereafter "the Grishchenko Patent").
The Hoffar patent discloses a piston coupling mechanism. It comprises a cylinder which has a slot through its wall in the lengthwise direction. A feed piston is received within the cylinder and coupled to a drill motor by a connecting plate which is secured to or integral with the piston. The connecting plate projects outwardly from the piston through the slot extending lengthwise of the cylinder and extends over substantially its entire length. The outer end is received between projections formed on the body of the drill motor. If the pressure of the fluid in opposite ends of the cylinder is unequal, the piston will be driven away from the high pressure end and toward the low pressure end, sliding along a sealing strip.
The Dommann Patent discloses a conduit provided with a movable "T" fitting. A slit extends longitudinally along the conduit and radially through the conduit wall. The wall portions of the conduit wall which defines the slit are provided with a tongue and groove joint. A C-shaped fastener clamps the wall portions together. The fitting-conduit combination is moved along the conduit as desired while at all times maintaining the fluid connection between the conduit and a connecting line which is connected to the fitting. The "T" stem discharges into the extensions to which connections or other supply means can be made. The conduit-fitting combination can be employed to supply air to move equipment, such as a long face mining planer.
The Murray Patent discloses fluid pressure devices. It comprises a collapsible resilient hose which is positioned between the walls and lies on the bottom of a track. The collapsible hose expands to an expanded condition when internally subjected to fluid pressure. A carriage is provided for cooperation with the hose and track. The carriage comprises a propelling roller placed between the walls of the track. A shaft extends through the roll on the shaft and bearing which is provided as a journaling roll on shaft. Pendants are fixed to the outer extremities of the shaft and they carry counter rolls at their lower ends in an aligned relationship. The object to be propelled is attached to the carriage. When pressure fluid is introduced to the interior of the hose on either side of the carriage, an unbalanced moment is set up about the axis of the rolls causing the pendants to tilt in the direction of the propelling force. The hose is adapted to be supplied with fluid under pressure to each of its ends. The ends of the hose are provided with fluid pressure-tight fittings to which supply lines are connected. The lines are in turn connected to a valve housing within which a reciprocable spool valve is mounted. A supply line admits fluid under pressure to the valve housing and the supply line comprises a branch that leads to a pressure reducing valve. The branch lines lead to the housing at opposite ends so that constant pressure acts at all times on both ends of the spool when the valves are closed.
The Granbom Patent discloses a pressure fluid cylinder. It comprises a cylinder and piston adapted to be moved by pressure fluid. In the cylinder wall, there is a longitudinal slot where a transmitting member is projected. The transmitting member is secured on the piston by a mounting plate. A sealing member has the form of a thin tape-shaped strip and is attached by magnets to close the slot. The sealing member is moved below on the transmitting member so as to permit the mounting plate to project through the slot.
The Leibinsohn Patent discloses a flow regulator. It comprises a core, an outer flexible sleeve, and a split ring presettable along the outer surface of the flexible sleeve for presetting the rate of flow of the fluid through the device. The fluid flowing through space is thus forced, where the sleeve is pressed against the core, to flow through the helical recess to pass from one side to the opposite side of the ring. The cross-section of this passageway depends on the location of the split-ring, and therefore the ring is preset to any selected position to fix the desired rate of flow.
The Grishchenko Patent discloses a pressure fluid actuator. It comprises a force transfer bracket and a flexible hose disposed within the interior of the actuator chamber and adapted for reciprocal movement. In the wall of the actuator chamber structure there is an elongated slot through which the transfer bracket projects upward and outward. It comprises rollers which are secured on the shaft for engaging with the flexible hose. As fluid pressure is introduced into the pressure compartment of the hose member on either side of the actuator through the end fitting, the hose member begins to inflate, thereby creating a displacement effect for the rollers of the transfer bracket and causing the bracket to move in a direction opposite to the fluid pressure introduction side. The movement of the transfer bracket is guided along the actuator chamber structure with guide plates and bearing rods.
The Haven Patent discloses a tensioning device for producing a linear pull. It comprises an outer tube of strands woven on the diagonal to form a plurality of helices, an inner tube, and two plugs. The inner tube is confined within the outer tube and ends of the outer tube are sealed by the two plugs. The fluid pressure to be applied within the inner tube is an ignitible gas-evolving pressure-producing material.
The Seinfeld Patent discloses a diaphragm mechanism for pump clutches. It comprises two stationary casing members with conduits for the fluid to be conveyed. The device is used as a seal transmission device.
The Russell-French Patent discloses a sealing apparatus for closing a slot in a track cover in which the shuttle of aircraft steam launching engines operate. Sealing means are disposed along the under margins of the slot. The sealing means are divided into opposite groups affixed to opposite sides of the slot, each group comprising a multiplicity of pliant finger members overlapping the finger members of the opposite group to provide an effective sealing means to prevent the escape of low pressure steam to the deck above.
The Gehringer Patent discloses an integral seal for an aircraft launching cylinder. It comprises a tow cart which pulls a cable connected to an aircraft that is to be launched.
The Akhavi Patent discloses a stripper clamp. It comprises an exposed roller for manually rolling along a flexible tube to express the tube's contents.
None of these prior art patents have disclosed a hose piston disposed inside a continuous flexible hose, thereby creating a fluid mechanism wherein the fluid pressure difference inside the flexible hose will force the hose piston to move along a given direction within the flexible hose, which in turn causes rollers of an external device to travel in a direction along the same line as the direction of movement of the hose piston. It is highly desirable to have a very efficient and also very effective design and construction of an apparatus for transporting objects along various lengths of movement.